Chapter II: On the Necessity of Faith

St. Thomas, 2.2, q. 2, a. 3-8; St. Alphonsus, II, 2; VI, 505; H. Ap., IV, n. 3; Billuart, de Fid., disp. 3; Pesch, n. 426-465; Lahousse, de Virt. theol., disp. II, c. V, a. 4; Viva, Thes. damn., P. I, prop. I.

424. Things to be noted beforehand. 1. A twofold necessity as regards salvation is distinguished, one of means, the other of precept: a) That is necessary by necessity of precept which, if omitted inculpably, does not harm salvation, as the real reception of the Eucharist. b) That is necessary by necessity of means without which, even if it is omitted inculpably, in the present order of Providence salvation cannot be obtained.

This necessity of means again is twofold: strict, if it can be supplied by no other means; thus sanctifying grace in the last moment of life is strictly necessary for salvation; broad, however, if another means of supplying is present. Thus, for example, charity can succeed into the place of baptism. Cf. n. 1451.

2. It is certain that HABITUAL FAITH is strictly necessary, by necessity of means, for eternal life. For no one can be saved without infused habitual justice. But the habit of faith is either a part or the foundation of this justice. Therefore. But this faith, in baptized infants and the perpetually insane, suffices for salvation, since it is equally certain that all dying with the grace of baptism become partakers of eternal life (Suarez, disp. 12, s. 1, n. 4).

Therefore the whole question concerns ACTUAL FAITH, and indeed the act of faith both internal and external, with respect to adults who enjoy the use of reason.

The internal act of faith can be either explicit or implicit. It is called explicit when one adheres to a revealed Truth apprehended in its own terms: for example, I believe that Christ is the Incarnate Word. It is called implicit when one adheres to a revealed Truth contained in another Truth apprehended in its proper terms: for example, I believe all things which are proposed by the Church as revealed.